Act I: "We still have three or four coworkers with plenty of spare parts."[edit]

Frustrated with Zoidberg's incompetence as a doctor, the Planet Express crew demand Professor Farnsworth to fire him. The professor refuses, and the crew question why Zoidberg was ever employed in the first place. A series of flashbacks reveal that Zoidberg first met and befriended Farnsworth in 2927, during a mission to kill a Tritonian yeti for Mom. During the mission, Farnsworth became susceptible to hypermalaria, a fatal, incurable disease which can either strike instantly or remain dormant for years. As a favour to Farnsworth for killing the yeti and saving his life, Zoidberg agrees to an arrangement: when Farnsworth begins to experience symptoms of the disease, Zoidberg will perform a mercy killing before the disease can fully manifest. As a result, Zoidberg was employed by the professor for the purpose of carrying out the task.

In the present, the professor begins to experience the symptoms of hypermalaria, and insists that Zoidberg must kill him by surprise. The crew catch Zoidberg attempting to murder the Professor, and restrain him with the professor's lab coat and imprison him. Zoidberg notices a single white hair on the professor's coat and deduces that he does not have hypermalaria. Rather, he has contracted yetiism after being scratched by the Tritonian yeti. The illness mimics the symptoms of hypermalaria, but results in its victims transforming into a yeti.

Zoidberg escapes and goes to Mom, exchanging a coupon for a free tanning session for the yeti's head so that he may use its pineal gland as an antidote. Meanwhile, the professor reveals the truth to the crew, who decide to kill him themselves, using the Murdolator, an elaborate Rube Goldberg mechanical killing machine. Zoidberg returns to announce his discovery to the crew, just as the professor begins transforming into a yeti. Zoidberg forces him to swallow the yeti gland, but this fails and the professor turns into a double yeti. The Murdolator is eventually destroyed and collapses on top of the professor, successfully curing him. As the crew goes to a tanning salon to celebrate, Zoidberg laments giving away his coupon. A grateful Farnsworth offers to treat Zoidberg to a free session, and they both depart as friends.

In its original U.S. airing on 18 August, 2011, the episode scored a 0.7 share among adults aged 18-49, and 1.382 million total viewers. This is down about 80,000 viewers from the previous week's airing of "Fry Am the Egg Man". [2]

This episode focuses on the relationship between Zoidberg and the Professor, who are shown to be good friends. This contradicts previous episodes, most notably "Teenage Mutant Leela's Hurdles", where the Professor's last words are, "I curse Zoidberg!" Of course, he may have been delirious (considering both the circumstances and the Professor's mentality).

This episode also jokes around with Zoidberg's medical competence; he is depicted as being (as usual) horrible with humans, but shows himself to be excellent with other alien races, most notably yetis. For example, Zoidberg is able to extract the Tritonian yeti's gland that will save the Professor's life in record time. Mom also says that Zoidberg is "the best there is if you need an alien hacked to pieces!... In the budget category."

This episode was originally titled "9/10ths of Zoidberg is Underwater".

Fry then gets "Garfield syndrome", a reference to Garfield the cat. He looks like Garfield and even says his phrase "I hate Mondays".

Fry then develops "Muppet gangrene". This causes him to act like Kermit the Frog and say that "It's not easy being gangrenous", referring to Kermit's famous refrain from "Bein' Green". He is also only seen from the waist up, a reference to a long list of popular puppet characters.

Finally, Fry gets an unknown condition that makes him look like a Smurf.

Near the beginning of the episode, The Professor and Zoidberg are depicted as feeding mice to owls, similar to how in modern-day life, people will throw bread crumbs to pigeons.

In a flashback to a military field hospital on Triton, Professor Farnsworth asks, "How bad is it, doctor?" and Dr. Zoidberg responds, "Super bad," alluding to the popular film, Superbad, which premiered a few years before this episode was produced.

While the Yeti is biting his head, Zoidberg says, "Crunch all you want. I'll make more." This is a reference to the slogan from an advertising campaign in the 1990's, for Doritos chips: "Crunch all you want. We'll make more."

During Zoidberg's attempts at murdering the Professor, Chet Atkins' version of the song "Mr. Sandman" plays over the scene.

"Stooge out" could also refer to her sons being "stooges", e.g. devoted followers who are used by Mom for her own purposes.

After her sons leave, Mom says "John Zoidberg...it's been a long time. How've you been?". While perhaps not intentional, this is very similar to the first lines said by GLaDOS in the video game Portal 2. Both characters share a few traits including passive-aggressive behavior and a publicly genial image that hides malevolent motives. Also, Mom's real name is Carol, a short for "Caroline", GLaDOS former human identity.

When Fry uses the phrase "believable hulk", it's a reference to the double-meaning of the word "incredible".

Methane is actually odorless. Since it is often mixed with other odorous compounds, people mistakenly assume that it smells bad.

It is possible that Zoidberg's species is capable of smelling methane.

When everyone grabs a vial of poison, a sixth gloved hand grabs a vial as well. In the next shot it is shown that this is Scruffy's hand, yet he isn't involved in the poisoning process.

Scruffy could have been kill check 6 (which seems likely, since the death wheel has six blades).

Scruffy is wearing gloves when he takes one of the vials of poison, but in the next shot when he commences the mercy killing, they're gone.

The vegetables in Bender's salad were cut with the blade from the death wheel after the poison had been dripped on it, yet the Professor is seen eating the salad at the end.

The poison was cyanide and is lethal in doses of 1.5mg per 1kg of body weight. A rough estimate would put only 1.4mg of cyanide on the blades when they cut the vegetables, so there wasn't enough for it to really affect the Professor unless he weighs less than 1kg/2.2lbs.

Actually with about 20 drops to the milliliter, and a specific gravity of 1.2 for cyanide solution, a drop would weigh around 0.06 grams so two drops would be 120 milligrams. Of course you could also argue that since there are six blades on the death wheel and only two of them were poisoned (assuming Hermes' and Fry's drop went on different wheels), there is a 4 in 6 chance that the blade that cut the vegetable wasn't poisoned although this number become smaller with each vegetable (assuming the previous one wasn't poisoned).

When the crew discover that Zoidberg had sand-crabbed his way out of his surgery, Amy looks out of the window and down to the street below, showing that his surgery is above the ground floor, but the hole he created is full of soil. If anything, the hole would just drop down to the floor below.

He could've fallen down to the floor below and sand-crabbed out again for the fun of it.

Mom seems rather surprised to see Zoidberg, but hasn't Mom seen Zoidberg with the Planet Express crew in the past?

The only other time when Mom and Zoidberg could have interacted was in "Future Stock" and even then they probably did not cross paths as he had sold his shares of PlanEx. Also in the past she may have mistaken him for another Decapodian.

They are seen interacting in "Three Hundred Big Boys" but Mom never indicates she doesn't recognise him, merely commenting on his "impression" of a poor person.

Yeti Farnsworth knocks the death wheel off-course, through Bender and off towards a wall, obliterating the Murdolator as it goes, but, when Farnsworth recovers underneath the wreckage, the death wheel is right on top of him.

When the Murdolator was collapsing, we didn't see where the death-wheel landed, so it could have landed on Farnsworth when the camera was on everyone else.

Bender uses a lighter to light his cigar, but it's been established in several episodes that he has one built into his hand.

Perhaps his hand-lighter was out of fuel and he simply hadn't gotten around to replacing it.

After Zoidberg cuts Leela in half, both her tank top and pants are frayed, even though if he only cut her once this could only happen if her pants were attached to her tank top, and if she were cut at the precise place that the two met.

Fry: Careful, Leela! [Leela turns to Fry.] He knows less about Human anatomy than I do. And I can't even find my own uterus!

Fry: It's not easy being gangrenous.

Hermes: I thought you were only gonna take out one vertebra!Zoidberg: Yeah, but did you ever play Jenga? Sometimes, you pull one and—[Zoidberg makes an exploding sound.]

Zoidberg: What started out as a pleasant afternoon of drugs and surgery has not gone as planned.

Man: We're over the drop zone, gentlemen. Might I suggest you jump out the door and poop yourselves.

Fry: I consider myself a reasonable man. Quick with a joke. Slow to anger. But Bender can't go on long car trips anymore an' I say Zoidberg must die!Hermes: People, please! [Hermes raises his arms.] Let's not overreact— [Hermes' body parts disconnect and fall on the floor.] Death to the crab!

Hermes: Professor, we need to talk! [Hermes raises his right fist.] Man-to-mob.

Fry: You're a terrible doctor! [Hermes has crossed his arms. Fry points at Zoidberg with his right hand three times. Amy puts the kidney in her left pocket with her right hand.] [on camera] Nobody wants to see you ever again![Professor Farnsworth enters.]Professor Farnsworth: Dr. Zoidberg, I want to see you right now!

The flashbacks reveal once again that people in the future do not age the same as people of the 21st century. In 2927, Professor Farnsworth would have been 85-86, yet appears youthful and is healthy enough for the rigors of military duty.

The tool Zoidberg uses to extract the Tritonian yeti's gland is the same one seen in "The Series Has Landed" when Zoidberg examines Fry.

Bender once again shows his love for cooking by making a salad before adding his drop of poison on the death wheel. It was established in "My Three Suns".

This episode establishes the fact that Zoidberg has been working for Planet Express for 80-some years. However, in "Insane in the Mainframe", the crew is celebrating Zoidberg's 10th year at the company.